Background

I agree with the concept of a “love formula” presented by Kruglanski et al. and thank the authors for their bold attempt to describe a new, comprehensive model of love that is essentially based on motivation and needs. Their idea of describing love primarily as a search for meaning and significance corresponds very closely to current research (including from our laboratory) on the motivation and reward system (see below), including the question of meaningfulness and relatedness; the recognition that love is an interpersonal positive emotion, in which approach motivation is an essential aspect, is also in line with current research. Their Significance Quest Theory is well presented, and the three-factor representation of love, according to which love is a matter of the attribution of merit and appreciation (of the beloved) as well as the magnitude of one’s own need for recognition – and arises precisely from this triad – is sound. It remains to be seen whether the formula actually works or whether the problem is approached in too much of a reductionist and mechanistic manner. However, the resulting question of what happens when one of the three factors is “zero” (namely, that love is no longer possible) is a very interesting ancillary issue.

While I agree with most of this, I would still like to highlight, expand on, and even disagree with some aspects.

Love and biology

Love is not only a psychological phenomenon but also a physical and biological one (e.g., Esch & Stefano, Reference Esch and Stefano2005; Marazziti, Palermo, & Mucci, Reference Marazziti, Palermo, Mucci, L, Aloe and L2021). Love is a motivation, but above all, it is a feeling. This feeling is based on the brain’s reward and motivation systems (Esch & Stefano, Reference Esch and Stefano2005; Esch, Reference Esch2022). Hence, the ABCs of happiness (and love) – ultimately, the three types of motivation – include approach/wanting (Type A), aversion/avoidance or relief (Type B), and finally, assertion/non-wanting (“not having to”); one could also say transcendence and inner joy or contentment (Type C). All three types are generated by the brain or have their origin there, and they change over a lifetime, have different functions, are dynamic, and merge into one another (Esch, Reference Esch2022).

While falling in love, including the passion, longing, and ecstasy that come with it, are primarily found in Type A, we find, in contrast, the feeling of comprehensive connection, here also a “WE” feeling, instead of pure self- or ego-centeredness, especially in the second half of life, or in Type C (Esch, Reference Esch2022). This change in reward and motivation happens over time, including in relationships. Accordingly, the C system is also called the affiliation system – it is associated with inner satisfaction and happiness, is less externally focused or “needy,” and yet is a flavor of love.

The task of the three types of motivation is to reward the “right thing at the right time, in the right place,” thus (unconsciously) aligning our behavior – as if on an invisible string – so that we do what is biologically appropriate for the individual but also for the species.

Basic needs and the greater good

When it comes to basic needs, as described by Kruglanski et al., their list – although they refer to Abraham Maslow (Reference Maslow1954) – lacks alternative interpretations, most notably the ERG model by Clayton Alderfer (Reference Alderfer1969). Alderfer, in contrast to Maslow, no longer envisions a pyramid of basic needs, nor do the different needs exclude each other, as one can be, e.g., in an intimate relationship and still suffer – such as being hungry. According to this, the essential human motivations are characterized by the desire for existence, relatedness, and growth.

Although these components primarily relate to the individual, it is possible to place them in a biological context: love would therefore not only be self-centered or dyadic, e.g., for securing one’s own existence, but also for the survival of the species as a whole. Type C motivation then even recognizes altruism and self-sacrifice or transcendence as defining principles. Correspondingly, with regard to the biological perspective, one could also speak of evolution for the need for growth, or of generativity, that is, of connectedness across generations. Furthermore, the need for relatedness with regard to the species could be translated into a necessity for reproduction, including mutual protection. In other words, for both the individual and the species, basic needs and the underlying motivations originating in the brain can be directly linked to the principle of love (Esch & Stefano, Reference Esch and Stefano2005; Esch, Reference Esch2022; Marazziti et al., Reference Marazziti, Palermo, Mucci, L, Aloe and L2021).

Love is healthy

Love is biologically desired, not only for the individual but for the entire “tribe.” This can be seen in the fact that it is healthy, rewarded with longevity and fewer illnesses, and statistically reduces mortality and morbidity in populations (e.g., Esch, Stefano, & Michaelsen, Reference Esch, Stefano and Michaelsen2024; Holt-Lunstad, Reference Holt-Lunstad2021; Levine & Cooney, Reference Levine and Cooney2018; Waldinger & Schulz, Reference Waldinger and Schulz2010). Indeed, it is true that the “ego” (which seeks meaning and significance) is strengthened by love, especially in youth or at the beginning of romantic relationships, which includes or is based on Type A motivation. Then, especially in midlife or when the youth needs to be protected, it becomes mutual support and stabilization, i.e., Type B (Karwetzky et al., Reference Karwetzky, Michaelsen, Werdecker and Esch2022). However, later in life, it is more about letting go, transcendence, and “inner peace,” or eudaimonia (Esch, Reference Esch2022). Love, therefore, grows over time; it changes, including its biological mission – what it purposes. At the end, there is even a final renunciation – passing on a legacy to descendants, across generations, lovingly, called generativity (McAdams et al., Reference McAdams and de St. Aubin1992).

Unconditional love

Love can be unconditional, just as connectedness and relatedness include an inherent component of “non-self” (Esch & Michaelsen, Reference Esch and Michaelsenin press). Thus, as described, in love relationships, too, there is a movement from the self to the family and then a further opening to the greater good over time, which is almost the opposite of self-centeredness. This movement, accordingly, goes from Type A to C (Esch, Reference Esch2022) and ultimately transcends into a spiritual-cultural dimension of health and connectedness (Esch & Stefano, Reference Esch and Stefano2011; Esch et al., Reference Esch, Stefano and Michaelsen2024; Esch & Michalsen, Reference Esch and Michaelsenin press; Listopad, Esch, & Michaelsen, Reference Listopad, Esch and Michaelsen2021) – undoubtedly a result and “flavor” of love.